Abstract
Consumption of tea is inversely associated with cardiovascular diseases. However, the active compound(s) responsible for the protective effects of tea are unknown. Although many favorable cardiovascular effects in vitro are mediated by epigallocatechin gallate (EGCG), its contribution to the beneficial effects of tea in vivo remains unresolved. In a randomised crossover study, a single dose of 200 mg EGCG was applied in three different formulas (as green tea beverage, green tea extract (GTE), and isolated EGCG) to 50 healthy men. Flow-mediated dilation (FMD) and endothelial-independent nitro-mediated dilation (NMD) was measured before and two hours after ingestion. Plasma levels of tea compounds were determined after each intervention and correlated with FMD. FMD significantly improved after consumption of green tea containing 200 mg EGCG (p < 0.01). However, GTE and EGCG had no significant effect on FMD. NMD did not significantly differ between interventions. EGCG plasma levels were highest after administration of EGCG and lowest after consumption of green tea. Plasma levels of caffeine increased after green tea consumption. The results show that EGCG is most likely not involved in improvement of flow-mediated dilation by green tea. Instead, other tea compounds, metabolites or combinations thereof may play a role.
Highlights
Consumption of tea is inversely associated with cardiovascular diseases
This study shows for the first time that epigallocatechin gallate (EGCG) is most likely not involved in tea-induced improvement of endothelial function in humans
EGCG plasma levels were highest after intake of EGCG and lowest after consumption of green tea, only green tea improved Flow-mediated dilation (FMD)
Summary
Consumption of tea is inversely associated with cardiovascular diseases. the active compound(s) responsible for the protective effects of tea are unknown. More than 80 studies with EGCG, which encompass a wide range of clinical applications, were registered on clinicaltrials.gov as of October 2016 It is largely unknown, whether the beneficial cardiovascular effects of EGCG in vitro can be reproduced in humans. Whether the beneficial cardiovascular effects of EGCG in vitro can be reproduced in humans To elucidate this matter, we investigated the contribution of EGCG to tea-induced changes in flow-mediated dilation (FMD). We studied the impact of a single dose of EGCG in three different application forms (green tea beverage, GTE, and isolated EGCG) on FMD in healthy volunteers. The results provide insights into the potential role of EGCG and other tea compounds in the beneficial cardiovascular effects of green tea in vivo
Sign-in/Register to view highlights & summary 
Published Version (
Free)
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
